upd78f0124hgba1-8et-a Renesas Electronics Corporation., upd78f0124hgba1-8et-a Datasheet - Page 95

• Manufacturer Part Number: upd78f0124hgba1-8et-a
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

5.1 Functions of Clock Generator
5.2 Configuration of Clock Generator
The clock generator generates the clock to be supplied to the CPU and peripheral hardware.
The following three system clock oscillators are available.
• High-speed system clock oscillator
• Internal oscillator
• Subsystem clock oscillator
Remarks 1. f
The clock generator includes the following hardware.
Control registers
Oscillators
The high-speed system clock oscillator oscillates a clock of f
by executing the STOP instruction or setting the main OSC control register (MOC) and processor clock control
register (PCC).
The Internal oscillator oscillates a clock of f
internal oscillation mode register (RCM) when “Can be stopped by software” is set by the option byte and the
high-speed system clock is used as the CPU clock.
The subsystem clock oscillator oscillates a clock of f
subsystem clock oscillator is not used, setting not to use the on-chip feedback resistor is possible using the
processor clock control register (PCC), and the operating current can be reduced in the STOP mode.
2. f
3. f
Item
XP
R
XT
:
: High-speed system clock oscillation frequency
: Subsystem clock oscillation frequency
Internal oscillation clock oscillation frequency
Processor clock control register (PCC)
Internal oscillation mode register (RCM)
Main clock mode register (MCM)
Main OSC control register (MOC)
Oscillation stabilization time counter status register (OSTC)
Oscillation stabilization time select register (OSTS)
High-speed system clock oscillator
Internal oscillator
Subsystem clock oscillator
Table 5-1. Configuration of Clock Generator
CHAPTER 5 CLOCK GENERATOR
User’s Manual U16962EJ3V0UD
R
= 240 kHz (TYP.). Oscillation can be stopped by setting the
XT
= 32.768 kHz. Oscillation cannot be stopped. When
Configuration
XP
= 2.0 to 16.0 MHz. Oscillation can be stopped
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